Derek Valentino, 40, who was a letter carrier for the Darby Post Office and a resident of Prospect Park, Pa., was found dead after participating in the swimming portion of the triathlon.
Neighbors told NBC Philadelphia that Valentino leaves behind his wife and two teenage boys. His mail route was in Collingdale, Pa. Co-worker knew him as "Rudy."
Philadelphia Police Lt. Joseph Walsh said the department's marine unit found the 40-year-old man in the Schuylkill River 5:30 p.m. Sunday south of the Columbia Avenue Bridge along Martin Luther King Drive.
Valentino was taking part in a sprint triathlon, cops said. He entered the river shortly before 8:30 a.m. with about 100 other athletes Saturday and never came out of the water, said authorities.
Officials know when Valentino entered the water because all participants wear an electronic chip that records their times when they step on mats going into and coming out of the water, reported the Daily News.
Lifeguards in kayaks said they had not seen anyone in any apparent trouble in the water.
Workers noticed that one of the racers didn’t cross the exit mat on the river and began checking triathletes individually. A search and rescue operation began immediately and lasted four hours before changing to “recovery mode.”
Philadelphia Police Lt. John Walker told the Daily News that Valentino had no history of health problems and nothing was suspicious in the circumstances of his death.
About 1,500 people were taking part in the event, which consisted of a .9K swim, 24K bicycle race and 5K run.
Once the search and rescue operation began, race officials turned the triathlon into a duathlon.
"We also didn't feel it was proper to ask our athletes to swim in the water knowing there was an ongoing search," Richard Adler, chief executive officer of Philadelphia Triathlon LLC, told the Daily News. "All of the athletes were very understanding."
This is the first time someone has died in this triathlon.
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